The Cold Spring Harbor Symposia on Quantitative Biology are held yearly at the beginning of June at the Cold Spring Harbor Laboratory (CSHL), Cold Spring Harbor, New York. They bring together approximately 300-400 scientists from all over the world to present and evaluate new data and ideas in rapidly moving areas of biological research. Each year, a topic is chosen that seems to be at a stage where general and intensive scrutiny and review is needed. The Symposia always seek to bring research workers from abroad, as well as the U. S., so as to ensure the wide scope and depth of the program and to take advantage of their specific contributions. They also seek to provide outstanding younger scientists, both graduate students and post-doctoral fellows, with an opportunity to participate and communicate with more senior scientists. The Symposia also seek to have participation from women and minority scientists. The Symposia bring together scientists who use a variety of approaches e.g., genetics, biochemistry, molecular biology, cell biology, and structural studies, to analyze problems in the area under discussion. The proceedings of the Symposia are published by the Laboratory and thus made available to a wider audience than the scientists who attend the meeting. The annual Symposia will continue to be planned to further the progress of advancements in biomedical science. This proposal request support for the period 2004 to cover the 69th Cold Spring Harbor Symposium which will focus on "Epigenetics." The meeting will address the molecular basis of epigenetic phenomena and their relationship to chromatin and chromosome structure and function.